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Chapter 4:Newton’s laws of motion describe the motion of the dolphin’s path. This photo was taken at the Lisbon Zoo.Jin Jang.original

Chapter 5:Total hip replacement surgery has become a common procedure. The head (or ball) of the patient's femur fits into a cup that has a hard plastic-like inner lining.NIADDK, 9AO4 (Connie Raab-contact); National Institutes of Health, via Wikimedia Commonsoriginal

Chapter 6:This Australian Grand Prix Formula 1 race car moves in a circular path as it makes the turn. Its wheels also spin rapidly—the latter completing many revolutions, the former only part of one (a circular arc). The same physical principles are involved in each.Richard Munckton from Windsor, Melbourne, Australiaoriginal

Chapter 7:How many forms of energy can you identify in this photograph of a wind farm in Sandesneben, Germany?Jürgen from Sandesneben, Germany. Wikimedia Commons.original

Chapter 8:Each rugby player has great momentum, which will affect the outcome of their collisions with each other and the ground.Oz, Flikroriginal

Chapter 9:On a short time scale, rocks like these in Australia's Kings Canyon are static, or motionless relative to the Earth.freeaussiestock.original

Chapter 10:The mention of a tornado conjures up images of raw destructive power. Tornadoes blow houses away as if they were made of paper and have been known to pierce tree trunks with pieces of straw. They descend from clouds in funnel-like shapes that spin violently, particularly at the bottom where they are most narrow, producing winds as high as 500 km/h. Location: Oklahoma 7 miles south of Anadarko.OAR/ERL/National Severe Storms Laboratoryoriginal

Chapter 11:The fluid essential to all life has a beauty of its own. It also helps support the weight of this swimmer.Terren, Wikimedia Commonsoriginal

Chapter 12:Many fluids are flowing in this scene. Water from the hose and smoke from the fire are visible flows. Less visible are the flow of air and the flow of fluids on the ground and within the people fighting the fire. Explore all types of flow, such as visible, implied, turbulent, laminar, and so on, present in this scene.Andrew Magill, Flickr

Chapter 13:The welder’s gloves and helmet protect him from the electric arc that transfers enough thermal energy to melt the rod, spray sparks, and burn the retina of an unprotected eye. The thermal energy can be felt on exposed skin a few meters away, and its light can be seen for kilometers.U.S. Navy photo by Mass Communication Specialist 2nd Class Kevin S. O'Brienoriginal

Chapter 14:(a) The chilling effect of a clear breezy night is produced by the wind and by radiative heat transfer to cold outer space. (b) There was once great controversy about the Earth’s age, but it is now generally accepted to be about 4.5 billion years old. Much of the debate is centered on the Earth’s molten interior. The discovery of radioactivity in rocks revealed the source of energy that keeps the Earth’s interior molten, despite heat transfer to the surface, and from there to cold outer space.

Chapter 15:A steam engine uses heat transfer to do work. Tourists regularly ride this narrow-gauge steam engine train near the San Juan Skyway in Durango, Colorado, part of the National Scenic Byways Program.Dennis Adamsoriginal

Chapter 16:There are at least four types of waves in this picture—only the water waves are evident. There are also sound waves, light waves, and waves on the guitar strings.John Norton

Chapter 17:This tree fell some time ago. When it fell, atoms in the air were disturbed. Physicists would call this disturbance sound whether someone was around to hear it or not.B A Bowen Photography.original

Chapter 18:Static electricity from this plastic slide causes the child's hair to stand on end. The sliding motion stripped electrons away from the child's body, leaving an excess of positive charges, which repel each other along each strand of hair.Ken Bosma, Wikimedia Commonsoriginal

Chapter 20:Electric energy in massive quantities is transmitted from this hydroelectric facility, the Srisailam power station located along the Krishna River in India, by the movement of charge—that is, by electric current.Chintohere, Wikimedia Commonoriginal

Chapter 21:Electric circuits in a computer allow large amounts of data to be quickly and accurately analyzed..Airman 1st Class Mike Meares, United States Air Forceoriginal

Chapter 22:The magnificent spectacle of the Aurora Borealis, or northern lights, glows in the northern sky above Bear Lake near Eielson Air Force Base, Alaska. Shaped by the Earth’s magnetic field, this light is produced by radiation spewed from solar storms.United States Air Force photo by Senior Airman Joshua Strangoriginal

Chapter 23:This wind turbine in the Thames Estuary in the UK is an example of induction at work. Wind pushes the blades of the turbine, spinning a shaft attached to magnets. The magnets spin around a conductive coil, inducing an electric current in the coil, and eventually feeding the electrical grid.Phil Hollman, Wikimedia Commonsoriginal

Chapter 24:Human eyes detect these orange “sea goldie” fish swimming over a coral reef in the blue waters of the Gulf of Eilat (Red Sea) using visible light.Daviddarom, Wikimedia Commonsoriginal

Chapter 25:Image seen as a result of reflection of light on a plane smooth surface.NASA/Chris Gunnoriginal

Chapter 26:A scientist examines minute details on the surface of a disk drive at a magnification of 100,000 times. The image was produced using an electron microscope.Robert Scobleoriginal

Chapter 27:he colors reflected by this compact disc vary with angle and are not caused by pigments. Colors such as these are direct evidence of the wave character of light.John Liu, Flikroriginal

Chapter 28:Special relativity explains why traveling to other star systems, such as these in the Orion Nebula, is unreasonable using our current level of technology.hal wimmersoriginal

Chapter 29:A black fly imaged by an electron microscope is as monstrous as any science-fiction creature.U.S. Department of Agricultureoriginal

Chapter 30:Individual carbon atoms are visible in this image of a carbon nanotube made by a scanning tunneling electron microscope.Taner Yildirim (The National Institute of Standards and Technology - NIST)original

Chapter 32:Tori Randall, Ph.D., curator for the Department of Physical Anthropology at the San Diego Museum of Man, prepares a 550-year-old Peruvian child mummy for a CT scan at Naval Medical Center San Diego.Samantha A. Lewisoriginal

Chapter 33:Part of the Large Hadron Collider at CERN, on the border of Switzerland and France. The LHC is a particle accelerator, designed to study fundamental particles.Maximilien Brice, CERNoriginal